MD80 FLT CREW RPTS WAKE TURBULENCE ENCOUNTER WITH PRECEDING B767-400 ON APCH TO RWY 28 AT ATL.

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THE PURPOSE OF THIS RPT IS TO DOCUMENT A WAKE TURB EVENT WHICH OCCURRED ON THE FINAL APCH COURSE FOR RWY 28 INTO ATLANTA. WE FLEW THE HONIE ARR AND WERE GIVEN A DSCNT TO 3500 FT ON DOWNWIND. THE BASE TURN RESULTED IN AN EXTENDED FINAL; WITH THE ACFT ASSIGNED 170 KTS AND CONFIGURED TO 15 DEG FLAPS. APCH CTL INFORMED US THAT THE ACFT WAS 6 MILES IN TRAIL OF A HEAVY ACFT (LATER DETERMINED TO BE A B767-400) AND CAUTION FOR POSSIBLE WAKE TURB. WE TRACKED SAID TFC BOTH VISUALLY AND ON TCAS. THE HEAVY TFC INTERCEPTED THE FINAL ABOVE OUR ALT AND STARTED DSCNT ON THE RWY 28 FINAL APCH COURSE. ON APPROX 8 MILE FINAL INTERCEPTING THE GS WE PERFORMED AN INSTANTANEOUS UNCOMMANDED ROLL R TO APPROX 60 DEGS ANGLE OF BANK. PF KICKED OFF THE AUTOPLT AND RECOVERED TO WINGS LEVEL. THE ACFT THEN PERFORMED AN INSTANTANEOUS UNCOMMANDED ROLL L TO APPROX 60 DEGS ANGLE OF BANK. PF AGAIN RECOVERED TO WINGS LEVEL. THE FLT CREW THEN INFORMED APCH CTL THEY WERE SLOWING THE ACFT FOR ADDITIONAL SPACING ON TFC AHEAD. APCH CTL RESTR US TO NO SLOWER THAN 160 KTS. WE WERE ALREADY AT 150 KTS; AND WITH NO MORE INDICATION OF WAKE TURB COMPLETED APCH UNTIL CONFIGURING AT 160 KTS. THE REST OF THE APCH AND LNDG WAS COMPLETED WITHOUT FURTHER INCIDENT. ON THE GND THE CREW INFORMED ATC OF THE EVENT. DISPATCH ALSO INFORMED OF INCIDENT. THE UPSET RECOVERY TRAINING RECEIVED DURING RECURRENT SIMULATOR TRAINING WAS/IS EXTREMELY APPLICABLE TO THIS EVENT. THE INSTANTANEOUS NATURE OF THE UPSET AND HOW IT LOOKS AND FEELS IN THE SIMULATOR WAS CONSISTENT WITH THE ACFT'S PERFORMANCE DURING THE WAKE TURB ENCOUNTER AND RECOVERY. ALSO; THE RECOVERY TECHNIQUE WAS EFFECTIVE. AUTOPLT OFF; RECOVER WITH AILERON; VERY LITTLE RUDDER.